BM 字符匹配算法--BM算法在进行匹配时，包含两个并行的算法，坏字符算法和好后缀算法，这两种算法的目的就是为了让模式串每次向右移动尽可能大的距离。-BM character matching algorithm- the BM algorithm during the match, contains the algorithm, two parallel bad characters algorithm and good suffix algorithm, the purpose of these two algorithms is move to the right in order to let the pattern string each time the distance as large as possible.